#define _CRT_SECURE_NO_WARNINGS 1

#include<stdio.h>

int fib(int x)
{
	if (x <= 2)
	{
		return 1;
	}
	else
	{
		int left1 = 1, left2 = 1;
		int  y = 0;
		for (int i = 3; i <= x; i++)
		{
			y = left1 + left2;
			left2 = left1;
			left1 = y;
		}
		return y;
	}
}

int main()
{
	int a = 0;
	while (~scanf("%d", &a) != EOF)
	{
		int b = fib(a);
		printf("fib = %d\n", b);
	}

	return 0;
}